Hybrid normal-reverse prism coupler for light-emitting diode backlight systems

Abstract

For the first time to our knowledge, a hybrid normal-reverse prism coupler was formed on the bottom surface of a light guide in a LED backlight system to achieve a thin, lightweight, LED backlight system. The hybrid prism coupler (HPC) simultaneously exhibits two functions: extraction of guided light from the light guide and focusing the radiated light from the light guide, corresponding to the optical functions of the prism and diffusive sheets used in conventional LED backlight systems. Therefore, using a HPC eliminates the prism and diffusive sheets that have been indispensable optical elements in conventional LED backlight systems, which consequently reduces the thickness of the LED backlight system by 40% compared with conventional systems.

Arrays of Lucius microprisms for directional allocation of light and autostereoscopic three-dimensional displays

“…Autostereoscopic 3D display. The ability of the Lucius prism array to directionally allocate the incident light intensity suggests its use in various optical devices [18][19][20][21][22][23][24][25][26] , such as dual-view or autostereoscopic 3D display [27][28][29][30][31] . To perceive a 3D image, human eyes must see different views (binocular disparity), allowing for the sensation of depth known as stereopsis after complicated processing in the brain 29 .…”

Effect of a light guide plate with lenticular-arrayed surface on optical output for backlight and illumination application

“…The LGP is a most important optical element in the edge-lit BLU, the function of which is to propagate lights from LED by total internal reflection (TIR) and distribute light emitting uniformly from the emitting surface of the LGP. Therefore, there have been many types of the LGP to be proposed [1][2][3][4][5][6]. In general, most LGPs have many microstructures on its top, bottom surface, or the both to frustrate TIR to let light emerge from the LGP inside.…”

Random microstructure generation of different aspect-ratios and orientation for the optical design of LED edge-lit backlight using a generalized molecular dynamics force model

“…Various microstructure shapes [1][2][3][4][5][6][7][8] are used on the base of the light guide to produce a high-brightness backlight for the light source of a liquid crystal display without its own emitting source. The difficulties in optical design to reach the high-brightness requirement lie not only in the shape design of the microstructure [2][3][4][5], which has a better ability to narrow the redirected light which hits the base of the light guide where the microstructures are imprinted, but also in the design of the microstructure distribution necessary to fulfill the basic uniformity requirement for the display [6][7][8].…”

“…The difficulties in optical design to reach the high-brightness requirement lie not only in the shape design of the microstructure [2][3][4][5], which has a better ability to narrow the redirected light which hits the base of the light guide where the microstructures are imprinted, but also in the design of the microstructure distribution necessary to fulfill the basic uniformity requirement for the display [6][7][8]. The latter, in order to fulfill the uniformity requirement, needs to combine the microstructure generation scheme into the optical design phase and iteratively obtain the optimal microstructure distribution [9][10][11].…”

“…The latter, in order to fulfill the uniformity requirement, needs to combine the microstructure generation scheme into the optical design phase and iteratively obtain the optimal microstructure distribution [9][10][11]. In order to meet both requirements, microstructures with different aspect ratios and different microstructure orientation should coexist in a distribution design [3][4][5], which significantly increases the difficulties of such an optical design. For example, the microstructure orientations might vary concentrically along the light emitting diode (LED), especially to eliminate the dark and bright bands between the regions of LED sources at inlet regions.…”